The attack happened at 2958 South 4575 West around 3:45 p.m. Police say the child was walking down the street with a friend to get his bike. The dog was following the whole time, and suddenly attacked. Police say the child's cheek was "bitten off" along with multiple wounds to the head and face.
The boy was taken to Pioneer Valley Hospital and then flown to Primary Children's Medical Center for treatment.
The dog, belonging to a neighbor who lives on the same street was taken into custody by animal control officers.
Police say the dog's owner left the dog in a kennel and doesn't know how the dog got out. The dog does not have any history of violent attacks.